Conformational and Reaction Dynamic Coupling in Histidine Kinases: Insights from Hybrid QM/MM Simulations

Histidine kinases (HK) of bacterial two-component systems represent a hallmark of allosterism in proteins, being able to detect a signal through the sensor domain and transmit this information through the protein matrix to the kinase domain which, once active, autophosphorylates a specific histidine residue. Inactive-to-active transition results in a large conformational change that moves the kinase on top of the histidine. In the present work, we use several molecular simulation techniques (Molecular Dynamics, Hybrid QM/MM, and constant pH molecular dynamics) to study the activation and autophosphorylation reactions in L. plantarum WalK, a cis-acting HK. In agreement with previous results, we show that the chemical step requires tight coupling with the conformational step in order to maintain the histidine phosphoacceptor in the correct tautomeric state, with a reactive δ-nitrogen. During the conformational transition, the kinase domain is never released and walks along the HK helix axis, breaking and forming several conserved residue-based contacts. The phosphate transfer reaction is concerted in the transition state region and is catalyzed through the stabilization of the negative developing charge of transferring phosphate along the reaction.Fil: Olivieri, Federico Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Burastero, Osvaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Drusin, Salvador Iván. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Defelipe, Lucas Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Wetzler, Diana Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Turjanski, Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Marti, Marcelo Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentin

JIRAM/Juno limb observations of H3+ in the mid- and low latitude Jovian atmosphere

NASA's Juno mission has been investigating Jupiter since August 2016, providing unprecedented insights into the giant planet's atmosphere. The Jupiter Infrared Auroral Mapper (JIRAM) experiment, on board Juno, performed spectroscopic observations of the H3+ emissions in both auroral regions (Dinelli et al., 2017; Adriani et al., 2017; Mura et al., 2017) and at mid-latitudes. In this work we analyse observations acquired over five orbits by the JIRAM spectrometer during the period from August 2016 to March 2017. In particular, during these observations, the spectrometer slit sampled Jupiter's limb over latitudes ranging from 60∘ equatorward, in both hemispheres. Limb spectra show typical H3+ emission features in the 3-4 μm spectral band, used to retrieve the H3+ densities and temperatures. Spatial resolution of the limb observations ranges between 50 and 130 km and is favourable for investigating the vertical distribution of H3+. Vertical profiles of H3+ limb intensities, in the 3-4 μm spectral band, are presented along with preliminary retrievals of the vertical profiles of H3+ volume mixing ratio (VMR). We compare our results with predictions from various atmospheric models. Acknowledgments The project JIRAM is funded by the Italian Space Agency

Infrared observations of Io from Juno

The Jovian InfraRed Auroral Mapper (JIRAM) on board the NASA Juno spacecraft is a dual-band imager and spectrometer, primarily designed to study the Jovian atmosphere and aurorae. In addition to its primary goal, JIRAM has been used to obtain images and spectra of the Galilean satellites, Jupiter's largest moons, when the spacecraft attitude was favourable to achieve this goal. Here we present JIRAM's first images and spectra of Io. These observations are used to characterize the location and possible morphology, and some temperatures, of Io's volcanic thermal sources; the identification of SO2 and the possible identification of other materials. A new hot spot/volcano is identified close to the South Pole of Io, and others are seen in lower latitude regions, which were previously unmapped. Images of the same region taken 2 months apart also show variations of hot spot intensity, possibly due to new lava flows or to lava flow breakouts

H3+ characteristics in the Jupiter atmosphere as observed at limb with Juno/JIRAM

NASA's Juno spacecraft has been orbiting Jupiter since August 2016, providing unprecedented insights into the giant planet's atmosphere. The Jupiter Infrared Auroral Mapper (JIRAM) experiment on board Juno has made spectroscopic observations of the trihydrogen cation (H3+) emissions in both northern and southern auroral regions (Dinelli et al., 2017; Adriani et al., 2017; Mura et al., 2017) and at mid-to-low latitudes (this paper). Observations targeting the limb of the planet from 60° North to 60° South latitudes were acquired with JIRAM's spectrometer in August 2016 and March 2017. We use these observations to characterize, for the first time, the vertical distribution of the H3+ emissions as a function of latitude across Jupiter's dayside. H3+ emission features in the 3-4 μm spectral band were used to retrieve the H3+ volume mixing ratio (VMR) and atmospheric temperatures as a function of altitude. The H3+ density profile has a quasi-symmetric distribution with latitude, decreasing from 5 × 104 cm-3 at 300 km to 2 × 103 cm-3 at 650 km altitude above the 1-bar level (column densities of 3.5 × 1012 cm-2 to 1.4 × 1011 cm-2, assuming a 700 km column depth). The H3+ VMR is higher in the Southern hemisphere than in the North with values at 500 km of 4 × 10-4 ppmv at 40°N and 8 × 10-4 ppmv at 40°S. Retrieved temperatures increase almost monotonically with increasing altitude, hovering around 400 K at 300 km and >900 K at about 700 km

Juno/JIRAM: Planning and commanding activities

In the context of space missions, where science is the most important goal, careful planning and detailed commanding are fundamental. The planning and commanding phases are activities whose complexity depends on the instrument characteristics, environmental constraints and scientific goals. The purpose of this work is to describe in detail these activities for the Jovian Infrared Auroral Mapper (JIRAM) on board the Juno spacecraft, a NASA mission to Jupiter. To maximize the scientific return, we fully employ the flexibility offered by the JIRAM operational modes to efficiently plan observations of various Jovian targets, in spite of the harsh Jovian radiation environment and the spinning state of the Juno spacecraft. Moreover, the JIRAM observations are limited by the challenging pointing and timing scheme of the mission, which impose constraints on both the observation planning and instrumental commanding

Luigi Settembrini. Periodico letterario educativo mensile. A. 2, n.1(1892)-A. 3, n.10(1894)

A.2, n.1(nov.1892): G. Olivieri, Ad Antonio Bartolini, P. 1-2 ; G. Olivieri, Prospero Viani, P. 2-11; R. Sabbatini, Ancora Quom o Quum?, P. 11-2 ; Pensieri del Settembrini, P. 12-3 ; E. Perito, Ad nubem, P. 13; F. Lagrance, Dell’educazione fisica, p. 14-15 ; Cronaca dell’Istituto L. Settembrini, P. 15-6.A. 2, n. 2(dic. 1892): G. Lanzalone, La morale nell’arte, P. 17-23 ; B. ( dal Bibliografo), Per i libri di testo nelle scuole elementari, P. 23-5 ; V. Notari, In Gutembergium artis typograficae inventorem, P. 25; Progressi della navigazione aerea, P. 26-8 ; Pensieri del Settembrini, P. 28-9 ; Il nostro concorso, P. 29 ; G. Lanzalone, La prima pioggia d’autunno, P. 30-1A. 2, n.3(gen. 1893): Bonghi, Una lettera del Bonghi, P. 33-4 ; G. Lanzalone, Ancora della morale nell’arte, P. 34-8 ; Pensieri del Settembrini, P. 38-9 ; C. Arlìa, Buon dì e tre anguille, P. 39-41 ; G. Lanzalone , All’amico G. Olivieri , P. 42-3 ; P. Lioy, Bagni e villeggiature, P. 43-5.A. 2, n. 4(feb. 1893): C. A. Alemagna, Per la morale nell’arte, P. 49-55.A. 2, n. 5(mar. 1893): R. Sabbatini, L’epistola di Saffo a Faone, P. 65-6 ; G. Lanzalone, Il drammaturgo(caricatura), P. 66-7 ; G. Lanzalone, Ancora per la morale dell’arte, P. 67-70 ; F. De Falco, Un’altra lettera!, P. 71-2 ; Il Settembrini, Per una petizione al Parlamento, P. 72; E. Perito, A mia sorella morta, P. 73-4.A. 2, n.6(apr. 1893): Il Settembrini, Petizione al Parlamento, P. 81-3 ; C. Arlia, Noterelle filologiche, P. 84-5 ; G. Bigoni, Ricordi Picentini (2 sonetti), P. 85 ; C. A. Alemagna, Lettera con annotazioni, P. 86-90 ; V. Caputo, Il giuramento, P. 90-1 ; A. Buscaino Campo, Il piè fermo di Dante, P. 92-3.A.2, n.7(apr. 1893): G. Lanzalone, Professori e maestri, P. 97-9 ; il Settembrini, Petizione al Parlamento, P. 100-2 ; Lista delle adesioni, P. 102-4 ; Guido Bigoni, Domenica Rusticana, P. 105 ; Pensieri del Settembrini, P. 105-7 ; Dal Gazzettino d’oro, Utili varietà, P. 107-8 ; G. Lanzalone, Al maggiore Vincenzo Notari, P. 108 ; V. Notarius, Risposta, P. 109 ; F. Accinelli, La poesia della vita, P. 109-10.A. 2, n.8(giu. 1893): C. Arlìa, Noterelle filologiche, P. 113-16 ; Guido Bigoni, La quercia del Tasso, P. 116 ; G. Lanzalone, La ginnastica con la neve, P. 116-17 ; Luigi Settembrini, Una lettera inedita di L. Settembrini, P. 118-19 ; V. Notaro, In Ariostum, P. 119 ; L’arte di respirare, P. 120-21 ; F. De Falco, Il suicidio e la religione, P. 122-24.A.2, n.9/10(lug.-ago. 1893): R. Mariano, Ad un banchetto nunziale, P. 129-132 ; G. Lanzalone, A Cristoforo Colombo, P. 132-34 ; C. Arlìa, Note filologiche, P. 135-36 ; G. Olivieri, Il terzo libro della vita di G. Cristo, P. 136-39 ; F. Persico, La pace, P. 140-41 ; L. A. Villari, Cesare Dalbono, P. 141-45.A.2, n.11/12(sett.-ott. 1893): Luigi Settembrini, Una lettera inedita di L. Settembrini, P. 153-54 ; A. De Leo, Vite di illustri salernitani, P. 154-62 ; G. Franciosi, I sogni, P. 162-63 ; A. Frabasile, Bozzetti ellenici, P. 164-70 ; L. A. Villari , Errori Giudiziari, P. 171-75 ; G. Lanzalone, Verismo, P. 175-76.A.3,n.1/2 (nov.-dic. 1893): M. Giordano, La pubblica educazione e l’ateismo, P. 1-4 ; il Settembrini, Concorso, P. 4 ; Per una forca conservata in un museo, P. 5 ; G. Lanzalone, L’Ora presente, P. 5 ; C. Mariano Pilar, Silvio Spaventa, P. 6-19 ; C. Arlìa, Note filologiche, P. 20-1 ; G. Grammatica, Ideale, P. 22 ; G. Olivieri, Funesta rimembranza, P. 31-2 ; G. Olivieri, La notte della vigilia del Natale, P. 32.A.3, n.3/4(gen.-feb. 1894): G. Lanzalone, E la nostra petizione?, P. 33-5 ; Dall’albo di Luigi Antonio Villari, P. 36 ; G. Olivieri, Una visita inaspettata, P. 37-46 ; A. Frabasile, Alla signora G. P., P. 47 ; M. Giordano, Il Governo, i Municipi e l’istruzione religiosa, P. 48-53 ; G. Lanzalone, Esercizi militari, P. 53 ; C. Arlìa, Note filologiche, P. 54 ; G. Lanzalone, Un dubbio proposto al prof. Sabbadini, P. 54-5 ; G. L., Risultato del passato concorso e concorso nuovo, P. 55-6 ; R. Galdi, Epistola di Catullo ad Ortalo, P. 57.A.3, n.5/6(mar-apr 1894): G. Lanzalone, Dell’educazione nelle scuole classiche, P. 65-70 ; G. L., Un epigramma di Leone XIII, P. 70-1 ; V. Caputo, Vita di borso, P. 72-6 ; C. Arlìa, Note filologiche, P. 76-7 ; G. Lanzalone, Amore, P. 78 ; Aniello Gaeta, Dulcissime Rerum, P. 79-81 ; Francesco De Falco, La duchessa Ravaschieri e il dormitorio, P. 81-2 ; Carmine Zottoli, Risultato del passato concorso e concorso nuovo, P. 82-6.A.3, n. 7/8(mag. – giu 1894): C. Arlìa, Note filologiche, P. 97-8 ; G. Lanzalone, Per il 1°Maggio, P. 98-101 ; M. Giordano, La libertà d’insegnamento e di coscienza, P. 101-10 ; L. A. Villari, Il capitano Tim- Tim, P. 111- 15 ; C. A. Alemagna, L’opera recente di Herbert Spencer, P. 115-16 ; Nicc. Castagna, Sospiro, P. 116 ; G. Cuomo, Sovra un passo del carme “I Sepolcri”, P. 117-20.A.3, n.9(lug. 1894): Concorso nuovo, P. 125 ; C. Arlìa, Note filologiche, P. 126-27 ; Il manicomio dei genii, P. 127 ; G. Lanzalone, Elena, P. 128 ; Giovanni Cuomo, Nunzio del giorno, P. 128-29 ; Giovanni Manfredi, Ofelia, P. 129 ; G. Lanzalone, Da Anacreonte, P. 139.A.3, n.10(ago. 1894): R. Sabbadini, L’anno della nascita di Gasparino Barziza, P. 141-42 ; G. Lanzalone, Il Discredito dei versi, P. 142-46 ; C. Arlìa, Note filologiche, P. 147-48 ; E. Perito, L’ultima rosa d’estate, P. 148 ; D’Aloja, L’arte e la critica, P. 149-51 ; Epigrammi, P. 151-52

On the clouds and ammonia in Jupiter's upper troposphere from Juno JIRAM reflectivity observations

We analyse spectra measured by the Jovian Infrared Auroral Mapper (JIRAM, a payload element of the NASA Juno mission) in the 3150-4910 cm-1 (2.0-3.2 μm) range during the perijiove passage of 2016 August. Despite modelling uncertainties, the quality and the relative uniformity of the data set allow us to determine several parameters characterizing the Jupiter's upper troposphere in the latitude range of 35°S-30°N. Ammonia relative humidity at 500 millibars varies between 5 per cent to supersaturation beyond 100 per cent for about 3 per cent of the processed spectra. Ammonia appears depleted over belts and relatively enhanced over zones. Local variations of ammonia, arguably associated with local dynamics, are found to occur in several locations on the planet (Oval BA, South Equatorial Belt). Cloud altitude, defined as the level where aerosol opacity reaches unit value at 3650 cm-1 (2.74 μm), is maximum over the Great Red Spot (>20 km above the 1 bar level) and the zones (15 km), while it decreases over the belts and towards higher latitudes. The aerosol opacity scale height suggests more compact clouds over zones and more diffuse clouds over belts. The integrated opacity of clouds above the 1.3-bar pressure level is found to be minimum in regions where thermal emission of the deeper atmosphere is maximum. The opacity of tropospheric haze above the 200-mbar level also increases over zones. Our results are consistent with a Hadley-type circulation scheme previously proposed in literature for belts and zones, with clear hemisphere asymmetries in cloud and haze

Detection chain and electronic readout of the QUBIC instrument

The Q and U Bolometric Interferometer for Cosmology (QUBIC) Technical Demonstrator (TD) aiming to shows the feasibility of the combination of interferometry and bolometric detection. The electronic readout system is based on an array of 128 NbSi Transition Edge Sensors cooled at 350mK readout with 128 SQUIDs at 1K controlled and amplified by an Application Specific Integrated Circuit at 40K. This readout design allows a 128:1 Time Domain Multiplexing. We report the design and the performance of the detection chain in this paper. The technological demonstrator unwent a campaign of test in the lab. Evaluation of the QUBIC bolometers and readout electronics includes the measurement of I-V curves, time constant and the Noise Equivalent Power. Currently the mean Noise Equivalent Power is ~ 2 x 10⁻¹⁶ W/√Hz

Detection chain and electronic readout of the QUBIC instrument

The Q and U Bolometric Interferometer for Cosmology (QUBIC) Technical Demonstrator (TD) aiming to shows the feasibility of the combination of interferometry and bolometric detection. The electronic readout system is based on an array of 128 NbSi Transition Edge Sensors cooled at 350mK readout with 128 SQUIDs at 1K controlled and amplified by an Application Specific Integrated Circuit at 40K. This readout design allows a 128:1 Time Domain Multiplexing. We report the design and the performance of the detection chain in this paper. The technological demonstrator unwent a campaign of test in the lab. Evaluation of the QUBIC bolometers and readout electronics includes the measurement of I-V curves, time constant and the Noise Equivalent Power. Currently the mean Noise Equivalent Power is ~ 2 x 10⁻¹⁶ W/√Hz

Fatality rate and predictors of mortality in an Italian cohort of hospitalized COVID-19 patients

Clinical features and natural history of coronavirus disease 2019 (COVID-19) differ widely among different countries and during different phases of the pandemia. Here, we aimed to evaluate the case fatality rate (CFR) and to identify predictors of mortality in a cohort of COVID-19 patients admitted to three hospitals of Northern Italy between March 1 and April 28, 2020. All these patients had a confirmed diagnosis of SARS-CoV-2 infection by molecular methods. During the study period 504/1697 patients died; thus, overall CFR was 29.7%. We looked for predictors of mortality in a subgroup of 486 patients (239 males, 59%; median age 71 years) for whom sufficient clinical data were available at data cut-off. Among the demographic and clinical variables considered, age, a diagnosis of cancer, obesity and current smoking independently predicted mortality. When laboratory data were added to the model in a further subgroup of patients, age, the diagnosis of cancer, and the baseline PaO2/FiO2 ratio were identified as independent predictors of mortality. In conclusion, the CFR of hospitalized patients in Northern Italy during the ascending phase of the COVID-19 pandemic approached 30%. The identification of mortality predictors might contribute to better stratification of individual patient risk